Method of and machine for treating blanks



May 7', 1929.

" T. B. CLARKE ETAL- METHOD OF AND MACHINE FOR TREQTING BLANKS 2 Sheets-Sheet 1 Filed Jan. 29, 1925 l/E N TUNE y 7, 1929- T. B. CLARKE ET AL 1,711,588

METHOD OF A ND MACHINE FOR TREATING BLANKS Fi-led Jan. 29, 1925 2 Sheets-Sheet 2 z I I V VII/IIIII/fl/II/I/II/I/I/IIIIIIIl/II/lIl/IIII/I11/1110. 15

I 713' 121 17 0? l 2:9 j

Patented May 7; 1929.-

UNITED STATES PATENT OFFICE.

'rnomns BAGGOTT CLARKE AND LESLIE mien BENNION, or LEICESTER, ENGLAND,

ASSIGNORS TO TINI'IIIDv SHOE MACHINE JERSEY, A. CORPORATION OF JEESE RY CQRl-ORATION, or rarn'nson, new.

' METHOD OF AND MACHINE son TREATING BLANKS.

of the blank to oin the straight edge. These blanks are usually died out to shape and then skived on both edges. Hitherto such skiv ing has commonly been done with a machine such as that shown in United States Let ters Patent No. 760,082, granted May 17 1904, upon an application filed in the name-of Scott, which comprises straight-edged knife, a

presser roll and a matrix roll, the matrix beingof a shape to permit the greater part ofthe 7 blank to be forced into it and to bend the margin of the blank into the plane of the cut of the knife. In, this machine the blank is usually fed with the convex'edge' toward the knife and the long axis of the blank'paral-lel to the edge of the knife. In the operation of the machine the leading margin is distorted and skived by a out which progresses toward the body of the blank, and the trailing margin is distorted and skived by a out which progresses out wardly toward the edge of the blank.

A machine which operates-in this manner is satisfactory when leather blanks are being skived, but is liable to produce an undesirable result when laminated blanks such'as those of fibre-board are encountered owing to-the tendencyof this material to rough up and to peel by reason of the fact that the knife in its first cut gets between the layers ofjfibre and tears them apart more or'les I In order to avoid this objectionable result, the present invention provides a method of beveling the margins of blanks which comprises feeding the blank a plurality of times to a skiving knife in such manner that in each case a trailing portion. only of the blank is skived. Such a method may conveniently be practised with two machines of the type of the patent, one machine" having a matrix shaped to permit the leadingedge (forexample the convex edge) of the blank to pass beneath the,

knife unskived and to raise the trailing edge (the straight edge) of the blank into the path of cut of the knife, and the second machinehav- 5,518, and in Great Britain February 22, 1924.

ing a similar matrix but shaped in this case to permit the straight edge of the blank (now the leading edge and already skived) to pass benea th the knife and to raise the coveX unskived edge (now the trailing edge) into the path of cut of the knife. 1th such a procedure the skiving is always done on a trailing edge of the blank, and no tearing or roughing upof the layers results.

In another aspect, the invention relates to a machine comprising a knife and a member for presenting a blank to the knife, said member having a matrix shaped to permit the leading portion of the blank to lie outside the path of cut of the knife and to distort a trailing portion into'said path whereby the trailingportion only of the blank is skived. And preferably this matrix will be so arranged as to pre sent the blank obliquely to the knife so that a ginof which is already skived, will be facili-,

tated. 7

Referring now to theaccompanying'd'rawings, i

Figure l-is a perspective of a portion of a Fi ure 3 is a 'lan of a knife a stiffener and a roll having a matrix shaped to cause the straight margin only ofthe blank to be skived. I

Figure 4 'is a plan similar to Figure 3but showing a matrix shaped to cause the curved margin of the blank to be skived, and

Figure 5 is a cross-section of the parts shown in Figure 4-. I

The machine shown in the drawings, exc'e pt for certain features presently to be pointed ont,'is' or may be substantially like that shown in. the patent. The blanks 100,,stacked in a magazine and acted upon by a presser 7, are pushed. one by one by a reciprocating slide 8 beneath a gate 9 and thence between a presser roll 11 and a matrix roll'l3 which seize theblanks and feed them to a stationary'lmife 15. The mechanisms for re- 'machine'by the use .of Whichthe methodof ciprocating the feed slide, for rotating the rolls and for operating the pre'sser are or may be the same as in the patented machine and will not be described since the details of their constructions form no partof the present invention.

In the patented machine, the blanks are fed with their long axes parallel to the axes of the rolls and to the edge of the knife; and the matrix is so shaped that the entire margin of the blank is skived at a single operation. The blanks, as has been explained, are commonly fed with their curved margins leading, so that each blank is skived by a out which progresses first from the edge of the blank inwardly across the curved margin and later outwardly across the straight margin, the middle portion of the blank remaining unskived. When a laminated blank such as one of fibre-board is operated upon in this manner, the knife in the first cutgets between the layers, tears them apart and breaks them off more or less as it passesup through them, with the result that the skived margin presents a roughened surface.

In order to avoid this objectionable result, the present invention contemplates feeding the blank twice to a skiving knife in such manner that in both cases only a trailing portion is skived, so that the knife is never in a position to enter between the layers and tear them apart. And in order to facilitate the action of the knife, as 'well as the feeding of a blank the leading margin of which is already skived,the blank is fed obliquely to the knife and rolls.

The method outlined above may be carried out bythe use of a single machine having interchangeable matrix rolls or having one matrix roll provided with matrices either of which may be caused to be operative, or

by the use of two machines each having a roll provided with a matrix of the proper shape. For convenience, the method will be described as being carried out by the use of two machines, the matrix roll of one machine being shown in Figure 3 and that of the other in Figure 4:.

The first machine has a roll provided with a matrix shaped to receive a blank, as inclicated in Figure 3, with its substantially straight edge trailing and lying at a suitable angle, for example fifteen degrees, to the axis of the roll and to the edge of the knife, the

leading portion of the matrix being of sufficient depth to permit the leading portion of the blank to pass unskived beneath the knife, and the desired trailing portion of the matrix decreasing gradually in depth so as to distort the trailing margin of the blank in the desired manner into the path of the knife. In this figure the outline of the stiffener and of the partly removed skiving is shown by the full and dotted lines 17, 19. The outline of the matrix coincides with the outline of the being then unevenly disposed to the line of feed. For holding a pile of blanks in this position one of the side walls of the magazine is providedwith a projection 25 positioned to engage behind that corner of the trailing edge of the stiffener which lies nearer to the rolls. The vertically movable guard or gate 9 may be provided with an extension shaped to fit the leading edges of the blanks projecting towards the operator at theright hand side of the magazine as shown in Figure 1.

The presentation of stiffener blanks at an angle to the knife, instead of broadside on as has been usual in this type of machine,-has

the effect of prolonging the life of the knife bet-ween shar 3611111 0 aerations' and facilitating the running ofthe machine. Only a small 7 length of the knife edge is in operation at any one time, as will be evident from an inspection ofFigure 3; and the angular position of the blank relatively to the knife edge produces a shearing cutting act-ion rather than a direct push of the material against it, this out progressing along the stiffener from one end to the other. Thus there is reduced to a minimum the sudden strain on the machine which is necessarily produced when a long edge of stiffener material engages the knife practically simultaneously over its whole length.

Blanks having one edge skived in the man ner whichhas been described with reference to Figure 3 are then passed through another machine, with their straighter edges (those already skived) leading, said other machine having a cavity roll such that the already skived straight edge passes clear of the knife and the curved (now trailing) edge is dealt with, This second operation is shown in Figures 4 and 5, in which the stiffener is indicated as before at 100, the knife at 115 and the lower feed roll containing the matrix at 113.

In Figure, 3 the cavity used will be of the nature shown in Figure 2-, being of depth sub-' stantially equal to the full thickness of the stiffener over its middle area and practically all along its leading edge indicated by the line19, and only beginning to taper into the cylindrical roll surface beyond (above, in Fig ure 3) the line 27,. The portion 21 having passed the knife edge has been split from the stiffener and the cut will be continued, as the stiffener advances, along the line 27.

In Figure 4 the stiffener 100 is being fed to a knife for the second time,'and the portion 121 is being removed, along the line 29. The

leading portionof the stiffener, having been already skived, will miss the knife; but in order to facilitate. the gripping 'ofpthat por tion properlyby the rolls, the matrlx 111 this case is conveniently provided with a gradual bevel along its corresponding leading edge. It will be notedthat since the second skiving has been completed atthe right hand side of Figure 4, the two skivings have merged leaving no ridge at the region corresponding to the unfinished portion indicated at T In Figure 5 the toothed upper roll used is shown skiving an extension on the gate 9 may be dispensed with, and at the sides the corners of the stiffeners nearest the rolls (left in Figure 1) may be positioned by a projection corresponding to above indicated, the other encs of the stiffeners abutting againstthe usual side walls of the magazine. For the second skiving an extension on the gate as indicated is preferable to position the already 'skived and now leading edges of the stilfeners and the projection 25 is set inwardly and back wardly to engage the curved sides of the stiffeners a short distance from the corner; in this case the other corners of the stifleners abut against the right hand side wall of the magazine.

The presentation of heel stiffener blanks with their main dimension inclined to the knife as above described has an important advantage when partly skived blanks are being dealt with in a subsequent skiving operation in that a portion of the blank which has not been reduced in thickness, for instance the portion indicated at 33 in Figure 4, will have been gripped by the rolls before any substantial resistance is encountered by the engagement of the knife with any portion that is to be skived in said subsequent operation. Also, whether the blank has been partially skived previously or not, a grip by the rolls is ensured upon the main portion of the blank throughout practically the entire skiving operation upon the trailing edge of the blank owing to the grip by the rolls upon part of the central and unreduced portion of the blank at the same time as skiving of the edge is being carried out opposite another part of the central portion which has by that time passed the rolls. In skiving stiffener blanks by the two stage method above indicated, the trailing edge the blank, being always unskived, presents a substantial thickness to the feeding plate, so that aid from this memher may be relied upon to ensure, upon-thesec ond stage, due entry of the leading corner of the stiffener well between the rolls with avoidance of tearing of thatthin portion.

" Although the invention has been described inconnection with a particular procedure in which the skiving cuts progress outwardly to ward the edge of the margin whiclris being skived, it should be understood that the invention is not limited in its broader-aspects to this particular procedure, since results which are practical can be secured, for example, by first feeding the blank endwise to a cutter which skives a trailing portion of the blank and then reversing the blank end for end and feeding it to a cutter which skives the remaining portion. And although a particular machine and a blank made of a particular material have been described, it should be understood that the invention is not li1nited in the scope of its application to either.

Having thus described our invention, what we claim as new and desire to secure by Let tors Patentof the United States is l. The method of beveling a portion of the margin of a blank which comprises distorting that portion only and skiving it by a draw out which progresses obliquely across said margin. p

2. The method of beveling the margin of a blank which comprises distorting one marginal portion of the blank, skiving said marginal portion by a out which progresses obliquel y with respect to the blank and outwardly toward the edge thereof and then distorting another marginal portion and skiving said second similarly.

portion by a out which progresses 3. The method of skiving the margin of a blank which comprises feeding the blank a plurality of times to a skiving knife in. such manner that in each case a trailing portion only of the blank is skived.

4. A machine of the class described having, in combination, a skiving knife and. means for feeding a blank to the knife, said means comprising a member having a matrix shaped topermit the leading portion of the blank to lie outside the path of cut of the knife and to bend a trailing portion into the path of out of the knife whereby the trailing portion only of the blank is skived.

5. A machine of the class described having, in combination, a skiving knife and means for feeding a blank to the knife, said means comprising a pair of rolls one of which has a matrix shaped to permitthe leading portion of the blank to lie outside the path of cut of the knife and to bend a trailing portion into the path of cut of the knife whereby the trailing portion only of the blank is skived.

' 6. A machine of the class described having, in combination, a skiving knife, and means for feeding a blank to the knife, said means comprising a member having a matrix,

5 to lie in said path whereby the trailing portion only of the blank is skived by a draw out.

7. A machine of the class described having,

in combination, a s'kiving knife, and means for feedlng a blank to the knife, said meanscomprising a pair of rolls one of which has a matrix adapted to present the blank obliquely to the knife and shaped to permit the leading portion of the blank to lie outside the path of out of the knife and to cause a trailing portion to lie in said path whereby the trailing portion only of the blank is skived by a draw out. p

In testimony whereof we have signed our names to this specification.

THOMAS BAGGOTT CLARKE. LESLIE HUGH BENNION. 

